The effect of the biofilm-forming <i>Lactiplantibacillus plantarum</i> F3-2 on improving lipid accumulation <i>in vitro</i>

Obesity correlates with gut microbiota dysbiosis, with beneficial microbial intervention emerging as a promising therapeutic strategy for obesity-associated metabolic disorders. In previous studies, we screened <i>Lactiplantibacillus plantarum</i> F3-2 (<i>L. plantarum</i> F3-2) with the ability to inhibit lipid accumulation, but its biofilm-forming capacity and consequent impacts on probiotic functionality remain uncharacterized. Based on this, this study characterized the biofilm formation capacity of <i>L. plantarum</i> F3-2, analyzing its structural organization along with extracellular matrix composition. Comparative evaluation between planktonic and biofilm-states was performed using <i>in vitro</i> models to assess differential responses in gastrointestinal tolerance and probiotic functionality. Results revealed <i>L. plantarum</i> F3-2 as a robust biofilm-forming strain, developing biofilms approximately 11 μm thick after 24 h of cultivation, with extracellular polysaccharides identified as the primary extracellular matrix component. <i>In vitro</i> assays showed that biofilm-state <i>L. plantarum</i> F3-2 exhibited superior gastrointestinal tolerance, HT-29 cell adhesion, and 3T3-L1 adipocyte lipid accumulation inhibition compared to planktonic cells. These results provide a foundation for developing high-efficacy <i>L. plantarum</i> F3-2 probiotic products targeting adipogenesis suppression.